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Dr. Walt Volland revised June 28, 2013 Energy transferred from a hot object to a cold object is called heat. This how hot and cold are defined. Heat moves from high temperature hot objects to lower temperature cold objects. When you touch something that feels hot to you heat (energy) is moving to you from the hot object. When you touch an object that feels cold like an ice cube heat moves from you into the ice cube. You are hotter at 98.6oF ( 37oC) and losing energy to the ice cube at 32oF (0oC ). Energy is labeled with many unit types that depend on the measurement system. The calorie, cal, is defined as the amount of energy (heat) needed to increase the temperature of one gram of water by 1oC. The kilocalorie, kcal, equals 1000 small calories. To make life more complicated Nutritional energy values are reported in dietetic calories or the big Calorie. The nutrition Calorie is really equal to the kilocalorie or 1000 cal. 1 C = 1000 calories = 1 kcal. The little calorie is so small that the calorie yield from a slice of buttermilk bread equals 80 C or 80,000 calories. This link provides Calorie values for thousands of food items. Specific heat is a physical property of materials. It is used to describe heat transfer. The specific heat of a material is an intensive property that is independent of the amount of a substance. It is defined as the amount of energy needed to heat one gram of the substance by 1 degree Celsius. The mathematical expression is Specific heat = calories / grams oC Specific heat is essential when designing engine cooling systems, constructing electronic circuits so they do not overheat, designing refrigeration equipment and everything that involves heat transfer. The amount of heat needed to increase the temperature of any object can be figured using this relationship.
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